engine miss, fuel odor, code 134 any help?

just got a 2000 chev 3500 crew 4x4 7.4 litre 145k. had a code 134 stored, as of yet its not returned. It takes a while to start on the first try, yet starts right up on the 2nd. its loading up with fuel abit. engine has a constant miss at idle, but still runs ok., just kind of aggrevating. where would be a good place to start on finding the fuel leak(smell seems to be in engine compartment, then the miss. with no present codes kinda seems like a shot in the dark. thanks

I would start with a fuel pressure test including watching the pressure when you turn the engine off. It will drop a bit but should hold pressure. With 145K, have the 02s been replaced?

//2000CAYukon

thanks, I dont know about the o2`s but more than likely. I checked the warrenty history and an incredible amount of stuff done. I think I`ve got it narrowed down to the no#5 injector. It wasn`t starving for fuel it was loading up.I seem to have steady spark, yet it runs rough at idle,and thats the one that makes almost no difference when you pull the plug wire. how difficult is it to change an injector? and has anyone had any luck with injector cleaner of any kind? thanks again.